Indian-American plant biologists Venkatesan Sundaresan, 73, and Imtiaz Khande, 40, didn’t really want to answer that.
In 2015, they were actually studying how plant embryos work at a cellular level, when they identified a set of genes in rice flowers that seemed to initiate it. When used properly, they realized that these genes could help rice become the world’s first engineered self-cloning plant.
while it is certain While fruits, berries, and weeds (such as blackberries and dandelions) reproduce asexually in the wild (or clone themselves), the world’s major food crops are naturally sexual. For more than 30 years, attempts to clone themselves have failed.
However, by the time Sundaresan and Khande isolated their set of rice genes and published their first paper on their research in 2015, something massive had changed.
In 2012, biochemist Jennifer Doudna and her fellow researcher Emmanuelle Charpentier created CRISPR-Cas9 “molecular scissors” (for which they will win the Nobel Prize in 2020).
Jeans can now be cut, cut and glued quickly, accurately and easily. This device revolutionized medical research, conservation efforts, food hybridization, and resilience-building in crops.
At the University of California, Davis, it gave two professors working on rice flowers a means to reach a long-awaited end.
Working with teams of researchers in France and Germany, in 2017, they successfully created a rice plant whose seeds grew as clones of the original plant. In 2018, he published a paper on his work in the journal Nature.
Since then, they have worked to increase the success rate from about 30% to 95%. The next phase will involve limited field trials.
Sundaresan and Khande have now won the prestigious $500,000 WinFuture Prize, awarded by Vietnamese manufacturing billionaire Pham Nhat Vuong’s WinFuture Foundation, for research that seeks to solve some of the world’s most pressing problems.
Because it’s not just about rice. “We are already working on maize, millet and mustard,” says Sundaresan. “The important thing here is that whatever you find in rice is a model. If it works with rice, it potentially applies to all flowering plants.”
Is it as dramatic as it sounds? Excerpts from an interview.
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, What were you trying to study when you realized you could give the world your first engineered self-cloning plant?
Sundaresan: In our laboratory we were trying to understand how embryogenesis in plants occurs. The beginning of plant life is the fusion of two cells – one from the pollen (male unit of the flower) and the other from the ovule (female unit). As in animals, this fusion miraculously creates an embryo, in this case within a seed, which can then develop into a baby plant.
We extracted the genetic data in the form of RNA, analyzed it, and found that some genes were turning on as soon as the two cells came together. They were master genes, which were active in sperm cells.
Khande: So we turned on those genes in the egg cells and ultimately an embryo was formed without the involvement of sperm. An egg cell with this one active gene can produce an embryo.
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, but it also won’t clone,
Khande: Absolutely. This is where our colleagues (Raphael Mercier from the Max Planck Institute for Plant Breeding Research in Cologne, Germany and Emmanuelle Guiardoni and Delphine Miulet from the French agricultural research center CIRAD) came in. They discovered that we could actually bypass gene mixing by removing any new genes – creating a process that did not resemble reproduction but more like normal cell division.
Simply put, once the process is complete, the genetic structure of the offspring is now exactly like any other body cell of the mother plant. We call this process synthetic apomixis.
Sundaresan: It is derived from the Greek words “apo” or “without” and “mixis” meaning “mix”. Apomixis is the way blackberries and other such plants clone themselves to reproduce asexually in nature.
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, And it’s not just about rice?
Sundaresan: The important thing here is that everything you find in rice is a model. If it works with rice, it potentially applies to all flowering plants.
Khande: I think we were very lucky that most of the things we tried actually worked. And we had the technology. First, next generation DNA sequencing. Then, CRISPR-Cas9. With that gene-editing tool, it is possible to achieve in a few months with extraordinary precision what previously would have taken decades, and end up without anything like the same degree of certainty.
Sundaresan: It was amazing to actually see it working in the lab. Apomixis is something scientists have been attempting for more than 30 years. I liked the fact that it was eventually solved by a team of two people from opposite ends of the subcontinent.
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, what comes next?
Sundaresan: The idea is to ultimately grow more using less resources, especially water and land.
This is just the beginning when it comes to gene editing at the embryonic level for plants. We could potentially make plants more drought-tolerant or disease-resistant. We can work to increase yields more than ever before as humans, to save forest land from becoming agricultural land.
Khande: I’m also working with potatoes. It’s a little different from cereals, but given how fast we have progressed in the case of rice, in four years instead of 10 to 15 as we estimated, I think it can progress significantly faster.
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, How would something like a self-cloning hybrid be created?
Sundaresan: In terms of challenges, the main thing that remains are field trials. Proof of concept is ready. Both Imtiaz and I now plan to work on other crops. In each crop we have to identify the same type of gene. We have already focused on maize and made good progress there. We have started a project with millet and Indian mustard.
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, So, can hybrids finally be subsidized and distributed in India?
Khande: China actually uses about half the land of India to produce almost twice as much rice. The reason for this is hybrid farming. About 50% of the rice grown in China is hybrid varieties, while in India the figure is about 8%.
The reason India and many developing countries are not doing this is because of the economics of hybrid seed production. They are really expensive and not feasible for farmers. Apomixis can change this because it is self-cloning. This could really have a huge impact, especially for smallholder farmers. This is where we are hoping our research will have the greatest impact.
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, What do you say about the insecurity that arises from this, in which the entire part of a crop may be equally susceptible to some disease or infection?
Khande: The short answer is that synthetic apomixis does not push agriculture toward a single genetic solution; This enables greater genetic diversity. This enables us to fine-tune any genotype and select traits before deployment. This means we can potentially tailor plants to specific environments and production systems, preserve some of the diversity that is being lost, and, if a pest or pathogen overcomes a particular genotype, rapidly recover and deploy alternative hybrids with different resistance profiles.
Safeguards such as availability of diverse varieties, resistance gene stacking and area-specific deployment will remain essential.
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, When you’re not working with plants, where will we find you?
Sundaresan: I like listening to Indian classical music. I also play the percussion instrument, which I believe is not uncommon among scientists. (laughing)
Khande: I like hiking. Here in the California Valley, we live in this amazing place. Drive 90 minutes and you’re in the mountains; Drive in the opposite direction and you’re at the beach. The desert is two or three hours away. I also like gardening. (laughs) It takes my mind off everything else…working with clay.
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Rear View: Back Story
* Venkatesan Sundaresan, 73, is from Tamil Nadu, grew up in Delhi and fell in love with science early on. “I chose physics in college because I was trying to understand how the world works,” he says, adding that he switched to biology at the PhD level. Growing up in an era of discussions of famine and ration shops, he says, “I wanted to contribute to the study of agriculture and help my country feed its people.”
* Khande grew up in the Kashmir Valley, and earned a master’s degree in immunology, and switched to developmental biology. He has a PhD in Plant Molecular Biology from the Indian Institute of Science (IISc), Bengaluru. He says, “I come from a rice farming family and our techniques have not changed for more than 40 years. This fact is extremely inspiring. I want to make hybrid varieties more practical.”
* Now as they move toward field trials for the world’s first engineered self-cloning plant, researchers plan to diversify. He has started work on other plants including maize, millet and mustard. Experiments have also started on potatoes. ,Given how fast we have progressed in rice, in four years instead of the 10 to 15 we had anticipated, I think we can progress much faster,” Khande says.
